package org.autumn.aqs;

import java.sql.Time;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.locks.AbstractQueuedSynchronizer;
import java.util.concurrent.locks.Condition;
import java.util.concurrent.locks.Lock;


// 自定义锁
public class AqsTest {



    public static void main(String[] args) {
        MyLock myLock = new MyLock();

        new Thread(() -> {
            myLock.lock();
            System.out.println(1);
            try {
                TimeUnit.SECONDS.sleep(1);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
            myLock.unlock();
        }, "t1").start();


        new Thread(() -> {
            myLock.lock();
            System.out.println(2);

            myLock.unlock();
        }, "t2").start();
    }
}

class MyLock implements Lock {

    class MySync extends AbstractQueuedSynchronizer {
        @Override
        protected boolean tryAcquire(int arg) {
            if (compareAndSetState(0,1)){
                setExclusiveOwnerThread(Thread.currentThread());
                return true;
            }
            return false;
        }

        @Override
        protected boolean tryRelease(int arg) {
            setExclusiveOwnerThread(null);
            setState(0);
            return true;
        }

        @Override
        protected boolean isHeldExclusively() {
            return getState() == 1;
        }

        public Condition newCondition(){
            return new ConditionObject();
        }
    }

    MySync sync = new MySync();


    @Override
    public void lock() {
        sync.acquire(1);
    }

    @Override
    public void lockInterruptibly() throws InterruptedException {
        sync.acquireInterruptibly(1);
    }

    @Override
    public boolean tryLock() {
        return sync.tryAcquire(1);
    }

    @Override
    public boolean tryLock(long time, TimeUnit unit) throws InterruptedException {
        return sync.tryAcquireNanos(1,unit.toNanos(time));
    }

    @Override
    public void unlock() {
        sync.release(0);
    }

    @Override
    public Condition newCondition() {
        return sync.newCondition();
    }
}
